Vehicles with hybrid drives are known from the prior art. Hybrid drives have two or more different drive sources, wherein power trains with an internal combustion engine and one or more electric motors have largely prevailed as a parallel hybrid or mixed hybrid. These variants are substantially parallel in the power flow arrangement of the engine and the electric drive and thus both a superposition of the drive torque and a control with purely internal combustion engine drive or purely electric motor drive is possible.
From DE 10 2010 030 573 A1 a hybrid drive with an automated transmission is known which has an internal combustion engine, which is drive-connected to at least one first transmission input shaft, with an electric drive having at least one electric machine, which is drive-connected to a second transmission input shaft, with at least one countershaft, with idler gears and fixed gears arranged in several gear set planes, with multiple gear shifting devices and with a transmission output shaft. In order to allow a great variability in terms of a gear set concept and the distribution and the number of electric and internal combustion engine gears, to keep the design and cost and to ensure efficient and comfortable operation, it is provided that the two transmission input shafts are arranged coaxially to each other, and that a gear shifting device connects the two transmission input shafts in an effective manner into one of their display positions, and shifts one gear into another shifting position. Thus, a partial transmission coupling is possible, which couples the two input shafts, the hollow shaft and the solid shaft, without a gear being shifted.
In order to achieve the most effective possible operation of the hybrid drive, transmission strategies are used, which flexibly use the electric drive depending on the situation, for example, for starting, as a starter generator or as a generator for power generation. From DE 10 2010 063 582 A1 a device for a power train of a hybrid vehicle is known, with a planetary transmission having the elements planetary carrier, sun gear and ring gear, wherein a first element of these elements of the planetary transmission of the fixed connection of a first transmission input shaft serves a first partial transmission of a transmission, and wherein a second element of these elements of the planetary transmission of the fixed connection serves an electric machine of a hybrid drive, with a first shift element, via which a third element of these elements of the planetary transmission in a first shifting position of the first shift element serves a second transmission input shaft of a second partial transmission of the transmission, to which further an internal combustion engine of the hybrid drive can be coupled, and can be connected in a second shifting position of the first shift element on the housing side or stator side, and with a second shift element, via which both transmission input shafts of both partial transmissions can be coupled to one another when the second shift element is engaged and when the second shift element is disengaged both transmission input shafts of both partial transmissions can be separated from one another. Thus, an electrodynamic starting and electrodynamic shifting is possible. In addition, the electric machine can be used as an integrated starter generator.
From the document DE 10 2014 202 381 A1 a method for operating a transmission device comprising a first input shaft with at least one shift element and a second input shaft with at least one shift element, wherein the at least one first and/or second shift element without participation in a drive power flow to minimize is/are closed by differential speeds in the transmission device.
The shift elements must be designed as synchronizers.